Interlocking sections of sheet piling driven into the ground is a popular, cost-effective method for installing barrier walls to prevent the movement of soils and limit groundwater migration. Typical sheet piling sections are made of steel plates and have connectors on the side edges. The sheet piling sections are installed sequentially by interlocking the connectors of adjoining sheet piling sections to form a continuous barrier. However, standard sheet piling barriers are not watertight since the interlocking joints provide a potential flow path for the passage of groundwater and other liquids. Attempts have been made to seal the joints between sections of sheet piling but these attempts have been difficult and expensive to implement and have not always provided a watertight seal.
Previously known methods for forming watertight seals between interlocking sheet piling sections use interlocking mechanisms that form cavities when connected to the adjoining section. After the sheet piling sections are driven into the ground, soil, vegetation and other materials that accumulate in the cavities when the sheet piling sections are driven into the ground are removed and the cavities are then filled with a sealant to form a watertight barrier. These methods encounter several problems that make it time consuming and expensive to form a satisfactory watertight seal. Before the cavities can be filled with a sealant, the materials accumulated in the cavities have to be removed using time consuming and labor intensive methods. However., once the barriers are installed in the ground, it is difficult to insure that all of the materials have been removed from the cavities. If any materials are left in a cavity, the sealant may not completely fill the cavity when it is added and a potential flow path is created for groundwater to pass through the barrier.
Several patents describe specially constructed sheet piling sections with interlocking joints which form a cavity that is filled with a sealing material. U.S. Pat. No. 3,302,412 to Hunsucker discloses interlocking thumb and finger elements which form a cavity between adjacent sheet piling sections that is filled with a sealant. U.S. Pat. No. 5,163,785 to Zanelli et al. employ an interlocking sheet piling mechanism shaped like claws that form a cavity for sealant material. U.S. Pat. No. 5,437,520 to Cherry et al. teach joints between pile-driven sheet piles having edge forms which interlock to form two cavities that are filled with a sealant.
Certain other types of prior constructions have been tried, but these constructions have required the cavities to be cleaned out after the sheet piling sections are installed before the sealant material is added. Thus, all prior constructions have the inherent disadvantages common to those above denoted relative to materials accumulated in the cavities formed by the interlocking joints when the sheet piling sections are installed.
Another disadvantage of previously known methods is inherent in the fact that they require specially fabricated sheet piles and cannot use standard sheet piles. Also, the interlocking joints of these specially fabricated sheet piles are easily damaged when installed in the ground, either making it difficult to fill the cavities with the sealant or preventing the joint from being properly sealed. An additional disadvantage specially fabricated sheet piles used in previously known methods is that they cannot easily be disassembled and reused because the interlocking connectors are damaged when the sheet piling sections are removed from the ground.